The invention relates to circular knitting machinery and in particular to the arrangement of cams and jacks for patterning.
The Applicants' earlier British Pat. No. 844,602 (corresponding to U.S. Pat. No. 3,046,760 and West-German Pat. No. 1,155,209) describes opposed cylinder knitting machinery with double ended needles, needle receiving sliders, and mechanism for transferring needles as required from one cylinder to the other. That Specification is particularly concerned with the production of both links-links and float stitch or similar patterning in the same courses.
The patterning is produced using rocking jacks which have upper and lower butts and can be rocked by selectors controlled by pattern drums or by ramps placed in the tracks of butts for the jacks. The ramps are used to push all lower butts of the passing jacks into the tricks to enable them to be cammed out of the trick subsequently in a selective manner by the selectors. Using the selectors, jacks which advance in a stream can be split up to follow two paths, one group of jacks being guided after engaging the selectors by their lower butts and the other group being guided, after failing to engage the associated selectors, by their upper butts. The jacks guided by their lower butts can be subjected to a further selecting operation, optionally after having converged into a single path with other jacks previously guided by their upper butts, after passing a further ramp so as to provide a pair of separate jack paths.
Thus links-links and float stitch patterning can be combined by first making a links-links selection (by selecting jacks to place butts of associated sliders onto a transfer cam) and then making a float selection (by selecting jacks to be raised to place butts of associated sliders onto a raising cam, float stitches being formed by jacks which have not been raised) whilst keeping the jacks involved in transfer above those raised for knitting in the lower cylinder. The jacks involved in transfer can thus not become involved in float stitch patterning. This arrangement has certain restrictions which, on the face of it, are inherent to the invention. Selection for links-links patterning must take place first, and once this is done, the jacks must be kept high. It would seem impossible for any selection to be made later which would require raising jacks to the level of those previously involved in links-links selection or, if this were done, the tracks for the upper butts of the jacks would meet and the jacks for rib and plain stitches would become mixed up and cease to be segregated.